Jonathan d



(No Model.)

J; D. MAWHOOD.

ROLLER MILL.

No. 398,339. Patented Feb. 19, 1889.

l@ Mur-RM1 J1/wanton UNITED STATES PATENT OFFICE.

`IONATHAN D. MAVHOOD, OF RICHMOND, INDIANA, ASSIGNOR TO TI'IE RICHMONDCITY MILL WORKS, OF SAME PLACE.

SPECIFICATION forming part of Letters Patent No. 398,339, dated February19, 1.889. Application filed April 2, 1888- Senal No. 269,31l.' (Nomodel.)

'To all 'whom it may concern:

Be it known that I, JONATHAN D. MAW- `HOOD, of Richmond, Iayne county,Indiana, -have invented certain new and useful Improvements inRoller-Hills, of which the folr lowing is a specification.

This invention pertains to improvements in roller-mills, and will bereadily understood from the following description, taken in connectionwith the accompanying drawings, in

Figure l is a side elevation of a double roller-mill, illustrating myimprovements, this view exhibiting certain roll-housing parts invertical section in a plane corresponding with the center of length ofthe roll-journals, and also a vertical section through certain of thehopper portions; Fig. 2, a plan oi one of the fixed roll-bones, the capof the box being removed; Fig. 3, a front elevation of one of themovable-roll hangings, the hand-wheel of the screw'M being omitted; Fig.Al, a horizontal transverse section of one of the movable-roll hangings;Fig. 5, a vertical transverse section of the agitator Y, this sectioncorresponding to the similar section appearing in Fig. l, except thatFig. 5 is upon a very much larger scale; Fig. 6, a horizontal section ofa portion of the feed-gate XV and agitator Y, and Fig.

7 a perspective sectional view ot portions ot' one of the roll-boxes andits cap.

The drawings illustrate but one side o'f'the roller-mill. The otherside, if shown, would appear the same. It is therefore to be understoodthat the parts appearing in the draw- `ings and often mentioned in thedescription in the singularnurnber will in practice be duplicated uponthe other side of the mill.

Many parts practically needed in a rollermill are omitted from thedrawings and description as not being speciallyv pertinent to thepresent improvements. Such partsmay,

. of course, be of any usual or suitable-construction.

Y I illustrate myimpr'ovements in connection with a doubleroller-mill-that is to say, a mill having two pairs of rolls; but theimprovements are applicable to mills having but a single pair of rolls.

In the drawings, A indicates the usual millframe5 B, the fixed ornon-adjustable roll; C,

' the fixed-roll housing, secured against the outside of the mill-frameand carrying the journal-boxes of the two fixed rolls; D, the boltssecuring this housing against the side of the frame; E, a pair of shaftspassing across the mill-frame and journaled in the {ined-roll housingsand provided at their outer projecting ends with eceentrics, this beingcommon construction, the intention pbeing, as usual, that these shaftsshall be provided with ,hand-levers or the like, by which they may beturned to eit'ect the quick opening and closing of the rolls; F,swing-nuts journaled upon these eccentrics; G, the movable rolls;

H, the journal-boxes of the movable rolls;

J, wrists pivoted to the mill-frame some distance below the movablerolls; K, levers having their lower ends adjustably secured to thesewrists, a threaded shank on the lever passing through the wrist andbeing engaged by a nut above and below the wrist, so that the lever maybe lengthened or shortened, the wrist forming the pivot of oscilla-Ition of the lever; La trunnion-pin journaled in a bearing across the topof the lever K and projeciingtherefrom at each side, the axis of thistrunnion-pin bei'ng parallel with the axes of the rolls and of the wrist'J M, an adj Listing-screw passing through and j ournaled in thetrunnion-pin at right angles to the axis of the trunnion-pin and passingthrough suitable apertures in the upper end of the lever K, the outerend of thisscrew being provided with a hand-wheel Aand with' a shoulderengaging against the outer face of the lever, the inner .end of thescrew passing to and engaging the appropriate swing-nut F; N, a leverdisposed substantially parallel to the lever K and pivoted upon theouter projectingends of the trunnion-pin L, this leverN beingof a hollowconstruction, so as to neatly inclose the lever K, and carrying upon itsupper end the movable-roll box H; O, a point of contact between thelower end of the lever N and a portion of lever K; P, a springscrew withits head abutting against the inner side of the lever N, and with itsthreaded portionenga-ging a nut; Q, a spring disposed in a'cup formedupon the iiXed-roll housing and opening outwardly, this spring abuttingagainst the back of the cup and presenting -IOO outwardly against therear face of the nut upon the spring-screw; R, the caps of therollboxes, each of these caps joining its box in a plane disposedhorizontally at one side of the journal and at theother side of thejournal in a plane disposed at an angle of about thirty degrees to theother plan'e; S, a large opentop chamber formed'in the box-cap R and fof a screw passing centrally through the cover into a frustum-shaped nutupon the under side of the cover; U, the end walls of the usual hopperstructure; V, the usual inclined rear wall of one of the hoppers, one oithe hoppers7 meaning the hopper pertaining to one of the pairs of rolls;NV, the usual automatic gate, forming in the illustration the front wallof the hopper, the lower free edge of this gate being contiguous to thefeed-roll and its upper edge being pivoted to the hopper; X, the usualfeed-roll, forming substantially a closure of the bottoni of the hopperformed by the hopper-back V and gate XV; Y, a swinging agitatorconsisting of a strip of metal disposed across from ond to end of thehopper and hung at its upper edge to the hopper-back V and having itslower edge contiguous to the periphery of the feed-roll, this agitatorbeing disposed within a facial rabbet in the lower inner edge of thehopperback V and forming substantially an articulated lower edge for thehopper-back; Z, a wire disposed along behind the agitator, near thelower edge thereof, and at the ends of the agitator extending forwardlyto and beyond the feed-gate XV, and there bent inwardly to engage theouter surface of the feed-gate; a., a flexible packing', as of rubber,secured against the inner ends of the hopper and turned inwardly toforni angles lying against the inward faces of the feed-gate andagitator at their ends, and extending a short distance along the innerfaces of gate and agitator, and preferably secured to those faces, thispacking descending to very n ear the periphery of the feed-roll; b, lugsor brackets projecting outwardly from the feed-gate .near its ends toserve as rests for the extremities of the wire Z; c, (see Fig. 5,) aclip-strip secured to the back of the agitator and extending the entirelength thereof and engaging the wire Z, and serving as a means forstiffening the agitator and for securing the wire in a hinge-like mannerto the agitator; and d, those portions of the wire Z which reachtransversely across the hopper from agitator to feed-gate and formconnecting-rods for transmitting motion from the feed-gate to theagitator.

The lever K is neatly boxed within the lever N, and the two levers,under certain conditions, form practically one lever oscillating uponthe wrist J. If we imagine the screw M as being absent, we can see thatthe combined lever K N would freely oscillate upon the axis of the wristJ, and thus carry practically a single lever, it will be seen that thescrew M, acting tangentially, serves to. prevent the outward movement ofthe lever, and also serves as a means by which the movable-roll boxesmay be adjusted toward the boxes of the xed roll, the spring andspringscrew tending to press the lever outwardly as far as the shoulderofv the adjusting-screw will permit. If we turn the adjusting-screw M inone direction, we force themovable rollV toward the xed roll, and if weturn the screw in the other direction we permit the spring to force themovable roll away from the iixed roll. In this manner we may adjust thegrinding distance between the rolls. The springpressure is adjusted bythe screw P.

The rotation of the eccentric-shafts E serves in the ordinary manner tomove the adj listing-screw M endwise when the rolls are to be quicklyopened, and when thisis done the springs force the rolls open. lVhen therolls are to be closed again, thc eccentrics pull inwardly upon thescrews against the torce of the springs. An admirable and simpleprovision is thus made for adjusting the grinding distances and for thequick opening and closing of the rolls; and particular attention shouldbe called to the dual duty of each IIO spring, duc tothe fact that whenthe eccentrics are operated to permit the rolls to openthe springsfurnish the roll-openin g force,1and that when the rolls are at work thesprings, acting upon the levers at points intermediate between theadjusting-screws M and the pivot-wrist J, tend to press the leversoutwardly against the shoulders on the adjusting-screws and against theouter surfaces of their foot-pivots, and thus take up all lost motionand prevent chat-tering of the movable-roll hangings, the tendency ofthe springs being to press the levers in the direction of the workingstrain and to prevent the reaction of the levers when the workingstrains are lessened. Y

It is important in roller-mills that the movable rolls should be capableof automatically opening when subjected to extraordinary strain, as whena foreign substance enters the mill. Provision for this is usually madeby means of springs, which hold the movableroll hangingst-o normalpositionthe springs 'the so-called combined lever and tend to press themovable roll away from the fixed roll, and that this tendency isresisted by the shoulder on the adj Listing-screw. This spring, whichtends to press the movable roll outwardly, also serves to resist theoutward movement of the roll and yield only in case of excessive outwardstrains upon the rolls.

By inspecting the right-hand portion of Fig. lit will at once be seenthat outward force' applied to the movable roll will cause the outerlever, N, to oscillate upon the trunnion-pin, the lower end of the leverN moving inwardly and compressing the spring. In short, the adjustableroll is carried by a v'composite lever, which lever is a lever of thesecond order when viewed as a means for permitting the automatic openingof the roll. In the first case the combined lever oscillates upon thewrist J, and in such oscillation the trunnion-pin Lis carried along withthe lever. In the second casethe wrist is without office as a pivot andthe trunnionpin Il keeps a fixed position, and the lever N oscillatesupon the trunnion-pin.

The cap R is held to its journal-box by a single bolt engaging the usualears upon that side of the box which is subjected to the wearing strainsunder motion, and the line of parting between cap and box at this sideof the box is at an angle, so that the part-ing-line in the bore doesnot present itself directly in the most useful part of thebearing-surface, the

'parting-line being considerably elevated above the center of thebearing. The other side of the bearing, not being subjected to wearin gstrains, I cut away quite freely at the center and form the largechamber S partly in cap and partly in box. The parting-space between capand box on this side of the journal I leave considerably open, and IfillV the space with a laminated gasket formed, preferably, of separatesheets of paper made up into pasteboard. This pasteboard serves inpacking the parting-joint and in distributing the lubricant placed inthe chamber above it, and as a means for permitting a greater closing ofthe cap upon the box by simply thinning the gasket by the removal of oneof its layers. The parting-joint between cap and box at the other sideof the journal is not formed by parallel surfaces; but the joint is leftopen near the journal and closed at the outside beyond the cap-bolt. Thecap is thus a lever of the second order acted upon by the bolt betweenits fnlcrum-point outside the bolt and t-he gasket on the other side ofthe journal, while the j oint-crack on the bolt side of the box is abovethe level of the gasket, and

thus less liable to cause leakage of lubricant. The cover T of thechamber S has a gasket of felt or similar soft material clamped betweenit and a frusttlm-shaped nut below it. The

frustum-shaped nut serves as a means for clamping the gasket and as ameans for directing and holding the cover to place.

The automatic feed-gate W' is to be arranged with an adjustable spring,tending to press its lower edge against the feed-roll. A preferredvconstruction and arrangement of this gate is found fully set forth in mypatent, No. 373,408, of November 15, 1887.

Material iiowing in the usual manner into the hopper strikes theautomatic feed-gate and causes it to properly open and furnish anoutlet-slot along the feed-roll, through which the material flows tothemill-rolls. This material under ordinary circumstances and constructionof hoppers often tends to clog at the ends of such hoppers and along thefoot of the hopper-back, thus interfering with thev performance of thefeed apparatus in causing the delivery of material to takeplace in athin stream uniform 'throughout its length along the feed-roll. Thematerial striking the gate IV gives to that gate a vibratory motion. Theagitator Y, free to oscillate upon itsl suspension-pivots, is connectedto the gate W by the connecting-rod portions CZ of the wire Z.

The consequence is that the vibratory motion of the gatewill becommunicated to the agitator Y, which will cause a shaking down ofmaterial otherwise tending to clog upon the lower portion'of thehopper-back.v The ends of the lower port-ion of the hopper and thecorners joining the ends and the other wall portions are formed by theflexible packing, a. This packing prevents the leakage of material pastthe ends of the gate and agitator; but that is not the main ofiice ofthe packing.

The angles otl the packing, being in contact with the feed-gate andagitator, receive motions from those parts, and the consequence is thatthe lower end walls of the hopper and the corner angles of the same arealways undergoing more or less vibrations, which will shake down thematerial and prevent clogging.

The packing, u, may be formed of rubber or.

cloth, or other flexible fabric, and it should be secured to placeloosely, so as to freely permit the requisite vibratory motions.

It is of course not essential that the adjusting-screw M should passthrough the trunnion-pin, each of these two parts having separateoffices.

I claim as my inventionl. In a roller-mill, the combination,substantially as set forth, of a mill-frame, a pair of mill-rolls, ahousing for the fixed roll, a lever pivoted to the frame and carrying atrunnion-pin, an adjusting screw for adjusting such lever upon its pivotand altering the position of said tru'nnion-pin, a lever carrying a boxfor the movable roll and pivoted Vupon said trunnion-pin, and a springarranged to act upon said levers at a point intermediate IOO IIO

between said trunnion-pin and the pivot of said first-mentioned lever.

2. In a roller-mill, the combination, substantially as set forth, of amill-frame, a pair of mill-rolls, a housing for the fixed roll, a-leverpivoted to the mill-frame and carrying at its upper end a tr unnionpin,means, substantially as described, for adjusting the distance betweenthe pivot of said lever and its trunnion-pin, an adjustingscrew foradjusting such lever, a lever pivoted upon said trunnion-pin andcarrying a box for the movable roll, and a spring acting upon both saidlevers.

3. In a roller-mill, the combination, substantially as set forth, of amill-frame, a pair of mill-rolls, a housing for the fixed roll, a leverpivoted to the mill-frame and carrying a trunnion-pin, a lever pivotedupon said trunnion-pin and carrying a box for the movable roll, a springacting upon both said levers, a nut, and an adj usting-serew engagingsaid first-mentioned lever and said nut to move said trunnion-pin towardsaid nut against the resistance of said spring.

i. In a roller-mill, the combination, substantially as set forth, of amill-frame, a pair of mill-rolls, a housing for the fixed roll, lever K,pivoted to the mill-frame, trunnion-pin L, j ournaled in said lever, adj us ting-screw M, engaging said lever and a nut, lever N, provided withbox II and pivoted to said trunnion-pin, spring Q, and spring-screw P.

5. In a roller-mill, the combination, substantially as set forth, of amill-frame, a pair of mill-rolls, a housing Afor the fixed roll, leverK, pivoted to the mill-frame and carrying a trunnion-pin, an adjListing-screw for adjusting said lever, hollow lever N, inclosing saidrst-mentioned lever and pivoted thereto and carrying a box for themovable roll, and a spring arranged to act upon both said levers.

6. In a roller-mill, the combination, substantially as set forth, of amill-frame, a pair of mill-rolls, a housing for the iixed roll, a wrist,J, in the mill-frame, lever K, carrying a trunnion-pin and provided atits foot with nuts engaging said wrist, an adjusting-screw to serve inadjusting said lever and altering the position of said trunnion-pin,lever N, carrying box H and pivoted to said first-men.- tioned lever,and a spring acting on both said levers.

7. In a roller-mill, the combination, sub.- stantially as "et forth, ofa mill-frame, a pair of millroll a fixed-roll housing, C, secured to themill-frame and carrying a box for the fixed roll, and an outwardly-opencup, a pivjusting-screw connecting said lever and a nut at thefixed-roll housing, spring Q, seating in said spring-cup, andspring-screw P, reaching from said spring to said lever.

S. In a roller-mill, the combination, substantially as set forth, of amill-frame, a pair of millrolls, boxes for said rolls provided withcap-receiving surfaces arranged in horizontal planes upon thenonfwearing side of the journals and in angular planes upon the wearingside of the journals, caps secured to said boxes and engaging saidsurfaces, and tangential chambers S, extending through the caps and pastthe non-wearing side of the journals into the boxes and below the levelof the bottom of the journals.

9. In a roller-mill, the combination, substantially as set forth, of amill-frame, a pair of mill-rolls, boxes for said rolls provided W1' thcap-receiving surfaces arranged in horizontal planes upon thenon-wearing side of the journals and in angular planes upon the wearingside of the journals, caps secured to said boxes and engaging saidsurfaces, tangential chainbers S in said caps and boxes at thenon-.Wearing side of the bearing, and gaskets interposed in thehorizontal joints between said boxes and caps and across said chambers.

10. In a roller-mill, the combination, sub@ stantially as set forth, ofa mill-frame, a'pair of mill-rolls, a feed-roll, a hopper, aspringpressed feed-gate forming a wall of the hopper and arranged tohave its edge act in conjunction with said feed-roll, a hopper-back, anagitator pivoted to such hopper-back and having its lower edgecontiguous to said feedroll, and connecting-rods engaging said agitatorand feed-gate.

ll. In a roller-mill, the combination, substantially as set'forth, of amill-frame, a pair of mill-rolls, a hopper, a feed-roll, a hopperback, afeed-gate with its lower free edge contiguous to Sal-id foodroll andwith its oppor edge pivoted to the hopper, and a flexible rocking at theends of tho hopper engaging thofeod-gato and extending at the foot o ftho food-sate from Lsaid food-gate to Said hopperbackl IOO 12. In aroller-mill, the combination, sub

Vstantially as set forth, of a mill-frame, a pair ,of mill-rolls,- ahopper, a feed-roll, feed-gate WV, hopper-back V, agitator Y, wire Z,engagins .Said agitator and ,food-sato, and Clip o, ohgaging suchagitator Aand Wire.

JONATHAN D. iviAvvnooD. iVitnesses:

oted lever supported by the mill-frame and carrying a box for themovable roll, an adf S. E. SWAYNE, H. E. ROBINSON.

IIO

